Re: [PATCH v6 05/13] hw/arm, target/arm: nested virtualisation on HVF

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 8/8/25 09:01, Mohamed Mediouni wrote:
> Signed-off-by: Mohamed Mediouni <mohamed@unpredictable.fr>
> ---
>   hw/arm/virt.c         |  9 ++++++---
>   target/arm/hvf-stub.c | 15 +++++++++++++++
>   target/arm/hvf/hvf.c  | 41 +++++++++++++++++++++++++++++++++++++++--
>   target/arm/hvf_arm.h  |  3 +++
>   4 files changed, 63 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 59e6c2b9df..91d8cd9363 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -817,8 +817,7 @@ static void create_gic(VirtMachineState *vms, MemoryRegion *mem)
>           g_assert_not_reached();
>       }
>   
> -    if (kvm_enabled() && vms->virt &&
> -        (revision != 3 || !kvm_irqchip_in_kernel())) {
> +    if (kvm_enabled() && vms->virt && (revision != 3 || !kvm_irqchip_in_kernel())) {
>           error_report("KVM EL2 is only supported with in-kernel GICv3");
>           exit(1);
>       }
> @@ -2281,7 +2280,8 @@ static void machvirt_init(MachineState *machine)
>           exit(1);
>       }
>   
> -    if (vms->virt && !kvm_enabled() && !tcg_enabled() && !qtest_enabled()) {
> +    if (vms->virt && !kvm_enabled() && !tcg_enabled()
> +       && !hvf_enabled() && !qtest_enabled()) {
>           error_report("mach-virt: %s does not support providing "
>                        "Virtualization extensions to the guest CPU",
>                        current_accel_name());
> @@ -2553,6 +2553,9 @@ static void virt_set_virt(Object *obj, bool value, Error **errp)
>       VirtMachineState *vms = VIRT_MACHINE(obj);
>   
>       vms->virt = value;
> +#if defined(CONFIG_HVF) && defined(__aarch64__)
> +    hvf_arm_el2_enable(value);
> +#endif
>   }
We don't have hvf_arm_el1_enable(). I think we just want to always
provide the most performant configuration to users.
IOW, we don't need hvf_arm_el2_enable(). I'd just always enable EL2
(if supported) in hvf_arm_get_host_cpu_features().